[PATCH v1 04/12] perf parse-events: Allow the cpu term to be a PMU
From: Ian Rogers
Date: Fri Jun 27 2025 - 15:25:16 EST
On hybrid systems, events like msr/tsc/ will aggregate counts across
all CPUs. Often metrics only want a value like msr/tsc/ for the cores
on which the metric is being computed. Listing each CPU with terms
cpu=0,cpu=1.. is laborious and would need to be encoded for all
variations of a CPU model.
Allow the cpumask from a PMU to be an argument to the cpu term. For
example in the following the cpumask of the cstate_pkg PMU selects the
CPUs to count msr/tsc/ counter upon:
```
$ cat /sys/bus/event_source/devices/cstate_pkg/cpumask
0
$ perf stat -A -e 'msr/tsc,cpu=cstate_pkg/' -a sleep 0.1
Performance counter stats for 'system wide':
CPU0 252,621,253 msr/tsc,cpu=cstate_pkg/
0.101184092 seconds time elapsed
```
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/parse-events.c | 37 +++++++++++++++++++++++++---------
1 file changed, 28 insertions(+), 9 deletions(-)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 7a32d5234a64..ef38eb082342 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -192,10 +192,20 @@ static struct perf_cpu_map *get_config_cpu(const struct parse_events_terms *head
list_for_each_entry(term, &head_terms->terms, list) {
if (term->type_term == PARSE_EVENTS__TERM_TYPE_CPU) {
- struct perf_cpu_map *cpu = perf_cpu_map__new_int(term->val.num);
+ struct perf_cpu_map *term_cpus;
- perf_cpu_map__merge(&cpus, cpu);
- perf_cpu_map__put(cpu);
+ if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
+ term_cpus = perf_cpu_map__new_int(term->val.num);
+ } else {
+ struct perf_pmu *pmu = perf_pmus__find(term->val.str);
+
+ if (perf_cpu_map__is_empty(pmu->cpus))
+ term_cpus = pmu->is_core ? cpu_map__online() : NULL;
+ else
+ term_cpus = perf_cpu_map__get(pmu->cpus);
+ }
+ perf_cpu_map__merge(&cpus, term_cpus);
+ perf_cpu_map__put(term_cpus);
}
}
@@ -1054,12 +1064,21 @@ do { \
}
break;
case PARSE_EVENTS__TERM_TYPE_CPU:
- CHECK_TYPE_VAL(NUM);
- if (term->val.num >= (u64)cpu__max_present_cpu().cpu) {
- parse_events_error__handle(err, term->err_val,
- strdup("too big"),
- NULL);
- return -EINVAL;
+ if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
+ if (term->val.num >= (u64)cpu__max_present_cpu().cpu) {
+ parse_events_error__handle(err, term->err_val,
+ strdup("too big"),
+ /*help=*/NULL);
+ return -EINVAL;
+ }
+ } else {
+ assert(term->type_val == PARSE_EVENTS__TERM_TYPE_STR);
+ if (perf_pmus__find(term->val.str) == NULL) {
+ parse_events_error__handle(err, term->err_val,
+ strdup("not a valid PMU"),
+ /*help=*/NULL);
+ return -EINVAL;
+ }
}
break;
case PARSE_EVENTS__TERM_TYPE_DRV_CFG:
--
2.50.0.727.gbf7dc18ff4-goog